What would be a good style bike to get a good cardio workout. I am looking at road bikes not mountain bikes.?

I can not stay in the lean forward position due to neck surgury

What would be the best, most cost effective way to transport mountain bikes with my small car?

I do not have any sort of roof mount available, nor a hitch. I really do not want to make any holes or anything in the body of the car either. I have tried to fit my bike inside but it is just too big- and my sister and I have plans to go on [...]

How would you control the speed for a pocket bike with electric motor?

Ive got this electric motor from an electric lawnmower and was wondering if I could make a pocketbike or some type of electric bike out of it. But how would I control the speed?

How can I figure out how fast my electric bike would go?

I’m trying to put together an electric bike, with parts from http://www.electricscooterparts.com/. I’m using a standard bike frame that weighs about 30 pounds. How can I calculate how fast a hypothetical electric powered bike will go just from looking at the voltages and amperages of the batteries/motors listed on the website?

Would changing and then leaving a bike gear for a few hours do serious damage?

My friend is pulling a prank on me, I’m in class but through a window I saw him change my bike gear from 5th to 2nd or 1st.
I won’t be able to reach my bike until later in the afternoon, about 2:45 pm, is leaving my bike jumped from 1st to 2nd gear for [...]